Power-storage and safety device for elevators.



N0. 838,322. PATENTED DEG. 11, 1906. W. P. GROOM.

POWER STORAGE AND SAFETY DEVICE PORBLEVATORS. Q

APPLIUATION IILEDAUG. s1, 19os.

3 SHEBTS-SHEET 1.

zvitmaooeoj QM M 33 12; lnoww u THE mmms PETERS cm, wAsmNuruN, n. c

PATENTED DEC. 11. 1906.

W- P. GROOM. POWER STORAGE AND SAFETY DEVICE FOR ELEVATORS.

APPLICATION FILED AUG. 31, 1906.

3 SHEETS-SHEET 2.

1n: NORRIS Psrnu co., wAsnmcnm, n. c.

PATENTED DEC, 11, 1906.

' W. P. GROOM. POWER STORAGE AND SAFETY DEVIGE'FORELBVATORS.

ARPLIOATION FILED AUGfSl, 1906,

a SHEETS-SHEET sl part of said means one or more reservoirs for 'WALLAGE P. GROOM, OF BROOKLYN, NEW YORK.

POWER-STORAGE AND SAFETY DEVICE FOR ELEVATORS- Specification of Letters Patent.

Patented Dec. 11, 1906.

Application filed August 31, 1906. Serial No. 332,726.

To all whom it may concern:

Be it known that I, IVALLAOE P. GROOM, a citizen of the United States of America, residing at the borough of Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Power-Storage and Safety Devices for Elevators, of which the following is a specification.

My invention relates to elevators or lifts for passengers or freight. Its object is, first, the supplying of a safety device, and, second, the utilization of that device for the storing up of power. Power must be used to lift either passengers or freight, and as nearly or quite all carried up come down again by means of the same apparatus that descending weight when conserved furnishes a power of no little consequence, which may be used in lifting other loads or for any other desired purpose.

Broadly stated, the invention consists in the employment of an air-compressor connected to an elevator-car in such manner that the descent of the car will compress air; of means for utilizing the pressure of that air thus compressed as a safety-check to control the movement of the car; also of utilizing as receiving and storing such compressed air, with their connections arranged to permit the utilization of such pressure, and particularly to effect the outletting of compressed air from and its reentry into the compressorcylinder, as desired, that it may be used to control the action of the piston and, through it and the cable attached to said piston and to the car, to also regulate the car movement.

It consists, also, in the instrumentalities which I employ to attain the ends sought and various combinations of such instrumentalities into operative devices.

Figure 1 is a diagrammatic view of an elevator-car located in a building and fitted with one arrangement of devices exhibiting my invention. As will be manifest, the val rious elements of the combination permit of almost endless variations, all within the spirit of the invention. Fig. is a central vertical section of a portion of the cylinder and piston which I prefer to employ. Fig. 3 is a cross-section of said cylinder, showing one end of the piston therein; Fig. 4 is an enlarged central vertical section of a part of a piston rod I may use. Fig. 5 is a cross-section of said piston-rod; Fig. 6 is a central vertical section of a part of the cylinder, showing a said attachment, showing also aportion of the car. Fig. 9 is a section of the upper part of the car, also showing in full lines a portion of an operatingcable, its method of attachment to the car, and an indicator, which informs the operator regarding the load sustained by said cable. Figs. 10 and 11 are respectively a side elevation and a cross-section of a valve I sometimes employ. Figs. 12 and 13 are respectively similar views of another form of valve which may be substituted for that of Figs. 10 and 11.

Sheaves 14, 15, 16, 17, and 18, Fig. 1, represent typically any of the ordinary means of moving a car 19 up and down between its guideways 20 by means of a cable 21. The power may be any of those well known, and an extended description is unnecessary. The pulley 1 1 (if that form is used) may be actu ated by steam or other power to draw the cable under sheaves 15 and 16 and over sheaves 17 and 18, to lift the car and on a reverse movement to lower the car.

22 is a cylinder which may be composed of sections bored out, flanged, and bolted together, as shown in Fig. 6. Its aggregate length is preferably a little more than onehalf of the travel of the car. It has an opening 23 at the lower end and an air-inlet port provided with a check-valve 24 at the upper end. To its bore are fitted the heads 25 26 of a piston 27, the body of which is preferably solid, the upper head concaved, and the lower conveXed, preferably, and to these heads followers 28 and 29 are fitted, space being left between their edges and the walls of the cylinder to permit cup-leather packings 30 or other packing to intervene.

The lower follower and the packing are held to head 26 by bolts 31, and a jam-nut 32, fitted to the thread of the piston-rod 33, secures follower 28 and its packing to the head 25. The body of the piston between the heads is preferably cut away, so that the bearings against the cylinder-walls shall be short in order that the piston may not bind if by any means the cylinder should become a little sprung or bent. The piston-rod 33 for the greater part of its length is preferably built of sections of tubing screw-threaded together and held from loosening one from the IIO other by a key 34, driven into position after ble21. This connector 36 passes up over sheaves 37 38, down under sheave 35, and up to a point 39 above the lim it of the piston rod-stroke, where it is firmlysecured. It is this arrangement which enables me to use a cylinder whose length is one-half that of the car movement, and though I might use a longer cylinder and attach the connector 36 directly to the piston that would largely increase-cost and prevent my obtaining the advantage I now gain by reason of the fact that one pound on the-car will substantially balance two at'the piston, thus enhancing the power of the loaded car in compressing air. If I should put in a double block in pla'ce'of the single-sheave arrangement and still further shorten the cylinder, there would be disadvantages in that construction, and therefore,though all of the'combinations are with in my field, I prefer that shown.

' At any convenient location I install a small high-pressure tank or reservoir 40, a low-pressure reservoir'41, and sometimes, as here, an intermediate reservoir 42, naturally, though not necessarily, placing the small high-pressure reservoir Well up in the building and the low-pressure in the lower basement or any out-of-the-way place, and I prefer to make the reservoir 40 about onehalf of the cubic capacity of the cylinder 22, reservoir 42, two or there times that cubic capacity for each elevator served thereby, and the low-pressure reservoir 41 still larger, as may be found convenient. I

From the upper end "of cylinder 22 a pipe 43 of small diameterextends to reservoir 40 and is provided'w'ith a throttle-valve 44 and a'check-valve 45,"and to obtain considerable length in very little distance I prefer to interpose a coil 46 in said pipe. A similar length and diameter of pipe returned on itself would to some extent answer the same purpose. Indeed, a very long pipe of small diameter mightserve asa crude safety device simply, Without using reservoirs. A second'pipe 47 extends from cylinder 22 to valve 55; a third, 48, from valve '55 to reservoir 41; a fourth, '59, from valve 55 to reservoir 42; a fifth, 49,*from reservoir 40 to reservoir 42; and a sixth, "50, from reservoir 42 to reservoir 41, pipe 49, of small diameter, being'p'rovidedwith a throttle-valve 51 and. pipe '50 with a pressure regulator or adjuster 52. It may be a pressurereducer or any other form of valve which will enable me to regulate in some degree the pressure in reservoir 42as, for instance, an ordinary safety-valve. If reservoir 42 were omitted, then pipe 49 would lead directly to reservoir 41.

55 is a three-way valve, (shown more in detail at Figs. 10 and 11,) in normal position. WVhen' it is turned slightly, port 56 will register with pipe 59 and port 58 with pipe 47. A further turn will bring port 58 into registry with pipe 48 and port 57 into registry with pipe 47, at the same time shutting off the passage to pipe 59. Instead of valve 55, I may substitute valve 60. It has stuffingboxes 61 at each end and three diametric passages 62 63 64, which may readily be so arranged as to successively OPBIICOIIlHlIlIllCt-g tions from pipe 47 to pipe 48, from 47 to 59, and from 47 "to the open "air, as desired, (with less degrees of tra vel than in the case of valve 55,) by connecting pipes 47 47 and 47 to pipe 47, 59 to 59, 48 to 48, and permitting to open to the outer air or as desired. These valves are provided with two drums 65 and 66. About the former a cable 67, carrying a weight 68, is wound, and an operatingcable 69 is reversely wound about drum 66. The operating-cable 69 passes about aseries of pulleys 7 O 71' 72 to bring it in line with the track ofthe car 19 and then upward parallel with said track and in close proximity with said car to a point 73, where it is fastened. The purpose of the cable 69 is to provide means whereby the elevator operator may actuate valve 55. If the cable ran directly through the car, it would afford such opportunity; but I prefer to add a more efficient means. To that end I mountsheaves74 and 75 upon the car, one on one side of the cable 69 and the other upon the other side thereof. Then upon an oscillatory bar 76, pivoted to the side of the car; I mount two other deeply-grooved sheaves 77 and 7 8, likewise arranged to register on the respective sides of cable 69 and so located as to insure that said cable shall run in their grooves as the car moves up and down.

Upon the inner end of the pivot of bar 76, which pivot is really an axle or shaft extended to a'point within the car, I attach a lever or drum-79,-and from this lever I run a cord down to and about a pulley 80 and to'a handpiece 81. A pull upon said handle will oscillate the bar 76, carry'pulley 77 to the left and pulley 78 to the right, thus putting a strain on cable 69, forming a bight therein, andoausingit to operate valve 55. As soon as cable 69 is relieved of this strain the weight 68 will return the plug of valve 55 to normal position.

'In addition to the connections named I prefer to connect reservoir 41 and cylinder'22 by a pipe 82, provided with a self-closing valve 83, the pipe 82 so opening into cylin der 22 that the piston will leave it uncovered when the car has nearly reached its upper limit of travel, and to automatically open this valve 83 I lead a cable 84 from the lever of valve 83 to and about pulley 85 and thence to a bell-crank lever 86, supported on a post 87 and connectedbylink 88 to a hinged arm 89, suspended near the path of car 19. In the car I mount a trip 90, which may project beyond its wall sufliciently to strike the end of arm 89 and through it and link 88 operate the bell-crank lever 86 to open valve 83. The trip 90 is mounted in a screw-threaded support and provided with a wheel or crank 91. By reversing that wheel the trip may be withdrawn so far that it will not make contact with the arm 89, and thus omit opening valve 83 in passing. Reservoir 41 is preferably provided with a safety-valve 53 and reservoir 42 with an outlet governed by valve 54 and also with a safety-valve 53. To insure that cable 69 is at all times kept in operative tension, I place in its path an idler-pulley 92, mounted on a threaded rod '93, furnished with a hand-screw 94, by turning which the pulley 92 will be raised or lowered to tighten or loosen cable 69. The cable 21 is preferably fastened to a plunger 95, surrounded by a spring 96, all mounted in a secure box 97 at the top of the car, and from the plunger 95 I extend a rod 98, attached to a lever 99, the long arm of which is linked to an indicator 100, moving in ways 101 and having a projection 102, adapted to trip the lever 103 of a bell 104 when the indicator is moved by the swinging of lever 99 on its pivot 105, though other forms of spring connection between the cable and the car might readily be employed.

The operation of these devices is as follows, it being premised that I prefer to make my piston and pistonr0d of a weight that will counterbalance the car to the extent desired, that I start with no pressure in the reservoirs, and that trip device 90 is run back, so that it will not strike arm 89: WVith a car weighing two thousand pounds a piston of about the same weight (having, say, one hundred square inches of surface at the head) would provide a workable counterbalance. As the car 19 rises by the pull of cable 21 the piston 27 dewith its load, furnishes ample force to accomplish the compression. Reservoir 40 will be rapidly filled with compressed air by continued operation of the car, and reservoirs 42 and 41 will be likewise filled, my preference being to set the pressure-regulator 52 so that it will open when the pressure in reservoir 42 is above sixty pounds and the safety-valve 53 so that it shall open when the pressure in reservoir 41 exceeds twenty. \Vhen the reservoirs are filled and there is a surplus of stored power, it may be taken through valve 54 for such other use as may be desired. When the power is thus stored and the car running with heavy load, I prefer to run out the trip. 90, and thereafter as the car approaches the upper limit of its travel that trip 90 will engage the arm 89 and force it and link 88 outward, thus swinging bellcrank lever 86 on its pivot and through cable 84 opening valve 83. Piston 27 will then have passed below the port from in cylinder 22, and. the result will be that the part of the cylinder above the piston will immet. iately fill with air at twenty pounds to the square inch above atmospheric pressure, which air will pass into reservoir 40 as the car goes down. If the weight of the car and its load should at any time be such as to make it undesirable to add this twenty poun-os to atmospheric pressure, the trip 90 maybe run back and the piston operated, as already stated. If with the appliances arranged and charged as described the load should at any time be too great for the primary lifting power, the operator can reac. ily take hold of handle 81 and with a slight pull swing. arm 76 and its sheaves 77 and 78. into the position shown in dotted. lines in Fig. 7, thus creating a bight in the cable 69 and causing it to rotate drum 66 and turn the plug of valve 55 until its ports 56'and 58, respectively, register with pipes 59 and 47, thus admitting air at, say, sixty pounr s pressure per square inch from reservoir 42 to aid the lifting of the car, or if that pressure be more than is necessary he can turn said plug so that port 58 registers with pipe 48, when air at only twenty pounds pressure would be admitted. He could thus add one thousand to three thousands pounds and upward to his lifting power; nor is it limited to the figures named, since by setting the safety-valves and regulators for other pressures he can provide for a greater reserve aid.

The safety feature is of great importance. If the operating-cable 21. or its connections should break, allowin the elevator-car to suddenly start down the shaft, the man in charge of the car would have nothing whatever to do (in fact, he would not have time to do anything) before the car would quickly but gently stop because of the elastic resistance afforded by the compressed air in the cylinder, which is constantly in commission. Then at his pleasure and to gratify others in the car he could let the car down slowly by simply pulling on the device 81 at his hand in the car, and thus operating valve 55, merely using the strength of a small boy.

stant spring 96 would begin to act.

This most satisfactory operation of my safety devices is brought about by the retarding of the passage of air out of the cylinder through long pipes of small diameter and the resistance afforded by the regulated pressures of contained air in the reservoirs with small inlets and small outlets, which positively require time to operate and reach a normal condition. To govern the length of time required for the desired action, I can set the several valves, as set forth, at any degree whatever that may be needed to accomplish automatically the purpose in view. In fact, I can very readily so set the valves that the car, even with the heaviest load, cannot come down, say, two hundred feet in less than one hundred and fifty seconds, notwithstanding the normal upruns of the car, including stops, are made in less than sixty seconds, unless valve 55 is brought into use by the operator in the car. tice, however, in moderately tall buildings the valve should be so set that the round trip of a car in rush hours could be made in about two minutes and ten or fifteen seconds provided the upruns are made in about fortyfive seconds, and this without recourse to the use of valve 55. In short, time is of the utmost importance. If the passage of air from a point where it is being compressed be retarded, the pressure mounts up very rapidly, and the brake-power increases in the same ratio and with the same rapidity, which is a prominent feature in my invention, and the arrangement of devices shown, including the throttle-valves, permits me to utilize this element of the time required to its utmost extent, since compressed air while prevented from escaping becomes almost as a solid to prevent the movement of a pistonagainst it, though preserving its wonderful elasticity in bringing the piston, and therefore the car, to rest. When the weight of the car and its load does not exceed the counterbalance thus provided in the piston and the increased pressure brought to its braking work, the operator must operate valve 55 to permit the car to move down; but, as already indicated, this would be readily done, since the mechanism described keeps the power of the compressed air at all times under his immediate and easy control.

As it is not only desirable but important that the operator in charge of an elevatorcar should know something regarding the load that cable 21 is carrying, I have interposed between that cable and the car a spring 96, and it is evident that the instant cable 21 is carrying less weight than required to fully operate the spring (because the flexible connector 36 is carrying largely) that in- In so doingit would move the plunger 95, and consequently lever 98, downward. That motion would swing lever 99 on its pivot 105 and In usual prac' raise the farther end and its attached indicator 100, which should at once be perceived by the operator but if through heedlessness it should not be noticed the projection 102 would in good time engage and trip the bellcrank lever 103, and the bell would command attention. The operator could then slow down the primary motor or operate valve 55 at his pleasure.

With a valve such as I could not only charge the cylinder with air at twenty pounds or sixty pounds or any other selected pressure, but I could also, if desired, relieve it of all pressure by turning the plug to a registry which would open a clear passage from cylinder 22 to the open air.-

What I claim, and desire to secure by Letters Patent, is

1. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod, a flexible connector at-- tached to said piston-rod and to said elevator-car, independently of the primary liftingcable, an air-reservoir, a connection from the compressor cylinder .to said air-reservoir, a check-valve in said connection, a second pipe or passage connecting said cylinder and said reservoir, a device for controlling the passage of air through said second passage, and means within the car, but connected with said controlling device, for op erating the same, substantially as and for the purpose specified.

2. The combination of an elevator-car, an air-compressor containing a reciprocating piston. a piston-rod, a flexible connector, attached to said piston-rod and to said elevator-car, independently of the primary liftingcable, an air-reservoir, a connection from the compressor-cylinder tov said air-reservoir, a check-valve and a retarding device in said connection, a second pipe or passage connecting said cylinder and said reservoir, a device for controlling the passage of air through said second passage, and means within the car, but connected with said controlling'device, for operating thesame, substantially as and for the purpose specified.

3. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod, a flexible connector attached to said piston-rod and to said elevator-car, independently of the primary liftingcable, an air-reservoir, a connection fromthe compressor-cylinder to said air-reservoir, a check-valve and coil in said connection, a second pipe or passage connecting said cylinder and said reservoir, a device for controlling the passage of air through said second passage, and means within the car, but connected with said controlling device, for operating the same, substantially as and for the purpose specified.

4. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod, a sheave on said pistonrod, a flexible connector passed under the sheave attached to said piston-rod, one end attached to a fixed support and the other to said elevator-car, independently of the primary lifting-cable, an air-reservoir, a connection from the compressor-cylinder to said air-reservoir, a check-valve in said connection, a second pipe or passage connecting said cylinder and said reservoir, a device for controlling the passage of air through said second passage, and means within the car, but connected with said controlling device, for operating the same, substantially as and for the purpose specified.

5. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod, a flexible connector, at tached to said piston-rod and to said elevator-car, independently of the primary liftingcable, a high-pressure reservoir, a connection from the compressor-cylinder to said highpressure air-reservoir, a check-valve in said connection, a low-pressure reservoir connected with said high-pressure reservoir, a pressure-regulator between said reservoirs, a second pipe or passage connecting said cylinder and said lowpressure reservoir, a device for controlling the passage of air through said second passage and means within the car, but connected with said controlling de vice, for operating the same, substantially as and for the purpose specified.

6. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod, a flexible connector, attached to said piston-rod and to said elevatorcar, independently of the primary liftingcable, a high-pressure reservoir, a connection from the compressor-cylinder to said highpressure air-reservoir, a check-valve in said connection, a low-pressure reservoir con nected with said high-pressure reservoir, an intermediate reservoir between said high and low pressure reservoirs, a pressure-regulator between said reservoirs, a second pipe or passage connecting said cylinder and said lowpressure reservoir, a third pipe leading fron'r said intermediate reservoir to the second pipe connected with the cylinder, a device for controlling the passage of air through said second passage and from the low-pressure reservoir to the cylinder and also from the intermediate reservoir to the said cylinder, and means within the car, but connected with said controlling device, for operating the same, substantially as and for the purpose specified.

7. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod, a flexible connector attached to said piston-rod and to said elevatorcar, independently of the primary liftingcable, a high-pressure reservoir, a connection from the compressor-cylinder to said high-pressure air-reservoir, a check-valve in said connection, a low-pressure reservoir con nected with said high-pressure reservoir, a pressure-regulator between said reservoirs, a second pipe or passage connecting said. cylinder and said low-pressure reservoir, a device for controlling the passage of air through said second passage and means within the car, but connected with said controlling device, for operating the same, a third pipe loading from said low-pressure reservoir to a port, which is located in the cylinder a distance above the bottom slightly in excess of the length of the piston, a valve in said third pipe for controlling the passage of air through it, a trip for said valve, adapted to be operated by the movement of the car when near the upper limit of its travel, a connection between said trip and said valve in the third pipe, and means connected with the car for operating the trip, all substantially as set forth;

8. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod, a flexible connector, attached to said piston-rod and to said elevatorcar, independently of the primary liftingcable, an air-reservoir, a connection from the compressor-cylinder to said air-reservoir, a check-valve in said connection, a second pipe or passage connecting said cylinder and said reservoir, a device for controlling the passage of air through said second passage, means within the car, but connected with said controlling device, for operating the same, a primary power-cable connected to the car, a spring interposed between said cable and said car, and an indicator in the car, con nected with said cable and adapted as described to be operated by the action of the spring, all substantially as set forth.

9. The combination of an elevator-car, an air-compressor containing a reciprocating piston, a piston-rod attached to the piston and to a sheave at the upper end of said rod, a flexible connector attached at one end to a fixed support, passed under said piston-rod sheave and over a sheave or sheaves attached to a fixed support or sup orts, and attached at the other end to said e evator-car, a high pressure air-reservoir, a-pipe or passage connecting the compressor-cylinder with the high-pressure air-reservoir and provided with a check-valve, a low-pressure air-reservoir, a second pipe or passage connecting the said air-reservoirs and provided with a pressureregulator, a pipe or passage connecting the low-pressure reservoir and the cylinder, and provided with a device for controlling the flow of air through such pipe, and'means within the car connected with said device for operating the same, substantially as and for the purposes specified.

10. The combination of an elevator-car, an air-compressing cylinder'containing a reciprocatingpiston, a pistonerod attached to said piston, aflex-ible connector attached to said piston-and also to thevelevatorecar, sheaves supporting and carryingsaid flexible connector, a highepressure airrreservoir, a pipe or passage connecting said high-pressure airreservoir and compressor-cylinder, said pipe or passage being provided with a check-valve and including a coil, a low-pressure air-reservoir provided with a safety-valve, a pipe or passage connecting the low-pressure reservoir with said compressor-cylinder and provided with a device for controlling the flow of air in such pipe and means for operating said de- Vice contained in the elevator-car and exteriorly connected with said air-flowecontroh ling device, substantially as and for the purpose set'forth.

11. The combination with an elevator-car, of a; sectional air-compressor cylinder containing a reciprocating piston, a sectional piston-rod, a sheave attached to the pistonrod, a flexible connector, a sheave supporting said connector, an air-reservoir, a pipe containing a check-valve and comprising a coil, connecting the cylinder and reservoir, a second reservoir, a pipe connecting said reservoirs, a pressureeregulator in said pipe, a safetyevalve, a pipe from the low-pressure reservoir. to the cylinder, an air-flow-controlling valve in said pipe, a cable connected to. the actuator of said valve, sheaves for guiding and means for tightening said cable, all constructed and arranged substantially as and for the purposes described.

12. The combination with an elevator-car of an air-compressor cylinder containing a reciprocating piston, a piston-rod attache to said pistonand carrying a sheave, a flexihle connector attached to said sheave, and also to the elevator-car, sheaves for supporting and carrying said flexible connector, a high-pressure air-reservoir, a low-pressure reservoir provided with a safety-valve, a pipe or passage connecting said high and low pressure air-reservoirs, and provided with a pressure-regulator, a pipe or passage connecting said low-pressure reservoir with said compressor-cylinder, and provided with a multiple-way valve for controlling the airflow in such pipe, means for operating said valve-Within the car and connections from thence to the valve, substantially as and for the purpose specified.

13. The combination of an elevator-car, an air-compressor cylinder, a heavy reciprocating pliston which is also a counterbalancingweig t forsaid car, a hollow sectional pistonrod, the sections of which are screwed together and held screwed together by knifeedged interior keys, said rod being attached to the piston and to a sheave, a flexible connector attached to a fixed support, passed under a sheave and over a sheave or sheaves, and attached also to the elevator-car, a highpressure air-reservoir, a valve-controlled pipe or passage connecting saidcylinder withsaid high-pressure reservoir, a low-pressure air-reservoir provided with a safetyvalve,apipe or passage connecting the reservoirs and provided with a pressure-regulator, a pipe or passage connecting said low-pressure reservoir with the air-compressor cylinder, a multiple-way valve, fitted in the run of such pipe, and means placed within the car and connecting exteriorly with said valve for operating it, substantially as and for the purposes set forth.

14. The combination of an elevator-car, a cable attached thereto and adapted to be connected with a primary ower, a verticallyplaced air-compressor cy inder, a piston .in said cylinder, adapted to constitute a counterweight to the car, a iston-rod, a sheave on said piston-rod, a flexible connectorhaving one end fixedly attached, the'other end attached to the car independently of the first cable, and its bight passed over fixedly-supported sheaves and under the sheave attached to the iston-rod, an air-reservoir, a pipe leading cm the cylinder to the said reservoir I and provided with avalve, a secondreservoir,

a connection from the first reservoir to the second, provided with a valve and a-pressureregulator, a safety-valve, a passage leading from the surrounding atmosphere to the upper part of the cylinder and controlled by a check-valve, a third reservoir interposed in the connection from the first to the second reservoir, but above the pressure-regulator, a multiple valve, connections from said multiple valve to the cylinder and respectively to the second and third reservoirs, a connection from the second reservoir to the lower part of the cylinder, a valve in said connection,means within the car for operating the multiple valve and connections between said means and said valve, a trip, means attached to the car for operating said trip, and connections between said trip and the valve in the lower cylinder connection, all substantially as set forth.

15. The combination of an elevator-car, an air-compressor provided with avalve-controlled air-inlet and containing a reciprocating piston, a piston-rod, a connectlon between the' piston-rod and the car whereby the rod will move in unison with the car, said connection being independent of the primary lifting-cable, an outlet-pipe leading from the compressor-cylinder at the same end as the inlet, and rovided with means for retarding the flow o air from saidcylinder.

16. The combination of an elevator-car, an air-compressor provided with a valve-controlled air-inlet and containing a reciprocating piston, arranged to constitute a counterbalance to the car, a piston-rod, a connection between the piston-rod and the car whereby the rod will move in unison with the car, said connection being independent of the primary two subscribing Witnesses, this 25th day of lifting-cable, aln outlet-pipe leading fom tile August, 1906. com ressor-cy inder at the same en as tie 7 inlet? and rovided with means for retarding g ALLAOE GROOM' 5 the flow 0' air from said cylinder. \Nitnesses:

In testimony whereof I have signed my 1 VVILLIAM B. COLE, name to this specificati0n,in the presence of i A. G. N. VERMILYA. 

